1. Field of the Invention
The present application concerns apparatus and methods for accessing resources. In particular the present application concerns apparatus and methods for accessing resources such as HTML scripts or bit maps included as part of larger application files.
2. Background Information
The Internet provides a convenient means by which data such as bit maps, HTML (Hypertext Mark-up Language) scripts, Java files and other resources may be accessed remotely. When files are accessed via the Internet, files are identified by a URL (Uniform Resource Locator). URLs comprise two parts, a scheme part identifying a protocol for downloading a resource and a scheme specific portion identifying the location of the resource. Thus for example an Internet address of the form ‘http’ followed by a semicolon (:), two backslashes (//), and a web address, such as ‘sw2000.com’ indicates that data located in the root directory of the computer corresponding to the address www.sw2000.com should be downloaded utilizing the hypertext transfer protocol.
Transfer protocols such as the hypertext transfer protocol (http:) and the file transfer protocol (ftp:) are file based protocols. This is to say the scheme specific portion of a URL using such protocols comprises data identifying a specific file stored on a computer.
Sometimes, however, it is desirable to access resources which are stored as part of a larger application file. The inclusion of such resources within larger files enables the entire file to be, for example, encrypted and check summed to ensure that the resource included within the application file is not maliciously or accidentally modified.
A separate protocol called the ‘res’ protocol has been developed by Microsoft to enable resources bound within larger application files to be accessed. As the resources included within larger application files cannot be identified by a file name. The scheme specific portions of a URL utilizing the conventional ‘res’ protocol therefore comprise an explicit URL identifying the location in the file system where the larger application file including the resource has been stored and data identifying the relative location within that application file where the particular resource is to be found.
The requirement that URLs utilizing the ‘res’ protocol include explicit URLs identifying the file location where an application is stored can cause difficulties.
Specifically, when an application is installed, the location in the file system where the application is stored is fixed by the application installer. This means that after installation references utilizing the ‘res’ protocol must be checked and if necessary amended so as to refer to the location in the file system where the file has actually been stored. Manual checking and editing is both time consuming and error prone and as a result the ‘res’ protocol has been little used.
In view of the above, there is a need for an alternative resource accessing technique for accessing resources included within larger application files which overcomes the limitations of the ‘res’ protocol.